When the SVS goes from stanby to on it will click, like my class d amp too, but no issue, not loud or annoying at all. When it goes to standby i dont know.
I did not hear the KC92, i have the KF92. The KC is more expensive and could be better, for my KF92 i payed ~1800€. It is much bigger as the SVS Micro 3000R and its clearly the better Sub! It playes louder and deeper and the bass notes sound more definded/ detailled. Hifi cost are exponentially, if it is worth it depends how much money you want to spend and i guell there are bigger but budget friendly 12" subs out there that are better than the kef but more ugly and ..bigger

But for the price and the size of the micro r it is very impressive and not bad! Loud enough to annoy any neighbours. Most content has no information below 20hz and what the svs delivers above the ia pretty good and detailed! And it has dsp. I dont know yet if i will replace my Kef KF92 or add to it. For my Room and situation (with kid) the svs is a very good choice i have to say! If the goal is detailed bass and a mini micro sub, the svs is a perfect choice, if loud output levels over ~80db is the goal, buy a bigger sub. Here a comparison foto: